> (defn fzipmap [f col]
> "Takes a col, applies f to each element and generates a
Note that the args should have come after the doc string!
On Tue, Aug 25, 2009 at 6:20 AM, Adrian
Cuthbertson<adrian.cuthbert...@gmail.com> wrote:
> For completeness we should include a loop/recur pattern;
>
> (defn fzipmap [f col]
> "Takes a col, applies f to each element and generates a
> hash map keyed on each element of col."
> (loop [col (seq col) mp {}]
> (if col (recur (next col) (assoc mp (first col) (f (first col))))
> mp)))
>
> user=> (fzipmap #(+ % 3) [1 2 3])
> {3 6, 2 5, 1 4}
>
> Regards, Adrian.
>
> On Mon, Aug 24, 2009 at 6:43 PM, samppi<rbysam...@gmail.com> wrote:
>>
>> Wonderful; I totally didn't know about zipmap. I've been using into
>> and map this whole time. Was it added right before Clojure 1.0? It
>> seems to be a lot faster than using into:
>>
>> Clojure 1.0.0-
>> user=> (time (into {} (for [i [1 2 3]] [i (+ 3 i)])) )
>> "Elapsed time: 0.705 msecs"
>> {3 6, 2 5, 1 4}
>> user=> (time (zipmap [1 2 3] (map #(+ 3 %) [1 2 3])))
>> "Elapsed time: 0.25 msecs"
>> {3 6, 2 5, 1 4}
>>
>> On Aug 24, 9:15 am, Dragan Djuric <draga...@gmail.com> wrote:
>>> (zipmap coll1 coll2) should be faster than (apply hash-map (interleave
>>> coll1 coll2)) and the doc description hints that's what it was made
>>> for.
>>>
>>> On Aug 24, 8:25 am, Garth Sheldon-Coulson <g...@mit.edu> wrote:
>>>
>>>
>>>
>>> > Welcome again.
>>>
>>> > Here's another way. Not sure if it's any more or less efficient, but it's
>>> > the way my brain works.
>>>
>>> > => (defn map-hashmap [coll f]
>>> > (apply hash-map (interleave coll (map f coll))))
>>> > #'user/map-hashmap
>>>
>>> > => (map-hashmap [1 2 3] #(+ % 3))
>>> > {1 4, 2 5, 3 6}
>>>
>>> > On Mon, Aug 24, 2009 at 2:18 AM, Stephen C. Gilardi
>>> > <squee...@mac.com>wrote:
>>>
>>> > > On Aug 23, 2009, at 8:21 PM, Stan Dyck wrote:
>>>
>>> > > I'm still new to this so bear with me.
>>>
>>> > > Welcome.
>>>
>>> > > I'm trying to apply a function to a seq-able thing to produce a
>>> > > hashmap.
>>> > >> So for instance say the function is (inc 3).
>>> > >> I'd like to write a function that does
>>>
>>> > >> [1 2 3] --> {1 4, 2 5, 3 6}
>>>
>>> > >> Can someone help me?
>>>
>>> > > Here's one way:
>>>
>>> > > user=> (into {} (for [i [1 2 3]] [i (+ 3 i)]))
>>> > > {1 4, 2 5, 3 6}
>>>
>>> > > --Steve
>> >>
>>
>
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